WARNING
The parent servers are not providing glue for all your nameservers. This means that they are supplying the NS records (host.example.com), but not supplying the A records.
That may cause some extra milliseconds in DNS. This will usually occur if your DNS servers are not in the same TLD as your domain
NS
Mismatched glue
0/7
The glue provided by the root servers does not match glue that provided by your authoritative DNS servers.
(ns3.cesky-hosting.eu. 86400 IN A 88.146.119.2) present at (88.146.119.2), missing at Parent
Nameservers A records
7/7
SUCCESS
Nameservers do include corresponding A records when asked for your NS records. This ensures that your DNS servers know the A records corresponding to all your NS records.
Nameservers report identical NS records
7/7
SUCCESS
The NS records at all your nameservers are identical.
SUCCESS
All of the NS records that your nameservers report are valid (no IPs or partial domain names).
Number of nameservers
5/5
SUCCESS
You have 3 nameservers. You must have at least 2 nameservers (RFC2182 section 5 recommends at least 3 nameservers), and preferably no more than 7.
Lame nameservers
7/7
SUCCESS
All the nameservers listed at the parent servers answer authoritatively for your domain.
Missing (stealth) nameservers
7/7
SUCCESS
All your nameservers are also listed at the parent servers.
Root missing nameservers
7/7
SUCCESS
All of the nameservers listed at the parent nameservers are also listed as NS records at your nameservers.
Nameservers on separate class C's
7/7
SUCCESS
Nameservers are in a different networks.
public IPs
7/7
SUCCESS
All of your NS records appear to use public IPs.
SOA
SOA record
SOA record is:
Hostmaster email
hostmaster.webtechnik.cz
Serial
1406877077
Refresh
16384
Retry
2048
Expire
1048576
TTL
2560
Serial agreement
7/7
SUCCESS
All your nameservers agree that your SOA serial number is 1406877077 That means that all your nameservers are using the same data.
SOA MNAME
3/3
SUCCESS
SOA (Start of Authority) record states that your master (primary) name server is: ns1.thinline.cz That server is listed at the parent servers, which is correct.
Serial value
1/1
SUCCESS
SOA serial number is: 1406877077 This appears to be in the recommended format of YYYYMMDDnn, where 'nn' is the revision. This number must be incremented every time you make a DNS change.
Refresh value
1/1
SUCCESS
SOA Retry interval is : 16384 seconds. This seems OK. (Values about 3600-7200 seconds is good if not using DNS NOTIFY; RFC1912 2.2 recommends a value between 1200 to 43200 seconds (20 minutes to 12 hours)). This value determines how often secondary/slave nameservers check with the master for updates.
Retry value
1/1
SUCCESS
SOA Retry interval is : 2048 seconds. This seems OK. (Values about 120-7200 seconds is good). The retry value is the amount of time your secondary/slave nameservers will wait to contact the master nameserver again if the last attempt failed.
Expire value
1/1
SUCCESS
SOA Expire time is : 1048576 seconds. This seems OK. (Values 604800 to 2419200 seconds (1-4 weeks) is good). RFC1912 suggests 2-4 weeks. This is how long a secondary/slave nameserver will wait before considering its DNS data stale if it can't reach the primary nameserver.
TTL value
1/1
SUCCESS
SOA Expire time is : 2560 seconds. This seems OK. (about 300 to 86400 seconds or 5 min - 24 hours is good). RFC2308 suggests a value of 1-3 hours. This value used to determine the default (technically, minimum) TTL (time-to-live) for DNS entries, but now is used for negative caching.
Info
DNS trace
Trace to webtechnik.cz
lookup webtechnik.cz at A.ROOT-SERVERS.NET(198.41.0.4) 9 ms
A.ROOT-SERVERS.NET(198.41.0.4) refer to a.ns.nic.cz(194.0.12.1)
lookup webtechnik.cz at a.ns.nic.cz(194.0.12.1) 99 ms
a.ns.nic.cz(194.0.12.1) refer to ns1.thinline.cz(91.239.200.243)
lookup webtechnik.cz at ns1.thinline.cz(91.239.200.243) 100 ms
got A record 'webtechnik.cz IN A 91.239.200.220' from webtechnik.cz(91.239.200.243)